Velocity Problem: John & Derek Meet - Solved in 2 hrs

[mike rach]

Homework Statement

John is on a bike starts his trip at a speed of v=18km/hr and two hours later Derek is on a motorcycle follows at a speed of 72km/hr. How far away from the start point they will meet? How is this problem solved?

Homework Equations

The Attempt at a Solution

 

[Dr. Courtney]

Express d(t) for each moving object.

Set them equal.

Solve for t.

Compute d(t) at that time.

 

[RyanH42]

V=x/t.So use this formula to reach "How many meter john travel in 2 hours"
Lets call it $x_1$.Now the time pass same both of them.
$x_1$+V_Johnt_John=V_Derekt_Derek
Use this equation to find solution.